Fruit tree scions are
propagated onto rootstocks by a process called "GRAFTING"
and also by
the process known as "BUDDING".

The rootstock is the most
important factor in determining the vigour and eventual size of
the tree. The choice of rootstock is therefore very important as
it will determine the suitability of the tree for the position
and the form in which you intend to grow it.

Below you'll find a list
of rootstocks and their characteristics. When buying a fruit
tree from a plant nursery it is important to know on to what
rootstock the original scion has been grafted on to, as
it will dictate the vigour and eventual size of your tree,
thereby influencing your eventual fruit crop.

If in
doubt then either ask the nurseryman for advice or check this
Fact-File that has been produced for you on
behalf of the Aeron Vale Allotment Society.

Table 1

Rootstock Types & Habits (Apple)

Very
Dwarfing

6ft
/2m

Dwarfing

8ft/2.5m

Semi
Dwarfing

10ft / 3m

Semi
Vigorous

14ft/4m

Vigorous

18ft / 5m

= Very Small

= Small

= Medium

= Large

Very Large

M27

others
available

M9

others
available

M26

others
available

M106

others
available

MM111

others
available

The most widely-used
rootstock in Europe in the 19th century was called
Paradise. During the 1920s researchers at East Malling
Research Station in the UK were the first to classify
rootstocks and develop new ones for specific purposes.
One of their first rootstocks was "M9", which was
developed from Paradise and another variety called "Jaune
de Metz". (It is possible that "Jaune" refers to the
golden yellow bark of this rootstock). Apple trees grown
on M9 rootstocks are small, and they fruit very early in
life - making this an ideal rootstock for commercial
apple orchards, and it is indeed probably the most
widely-planted of all rootstocks. East Malling Research
Station, in conjunction with some other UK research
stations at Merton and Long Ashton developed a range of
virus-free rootstocks of which M27, M9, M26, MM106, M7,
MM111, and M25 are in widespread use today. Note that
the numbers in the East Malling series have no relation
to the size of the tree - M27 and M26 produce trees
which are respectively smaller and larger than M9!

The examples listed
above are of the most popular UK apple rootstocks
which are well-known, smallest (1) to largest (5)

here is a little
more general information about them:

M27

Very small indeed;
around half the size of M9. Tree needs full support.
Fruit size reduced slightly. Moribund in wet soils. Very
little pruning is required once the tree is full size
(around 5ft high; produces perhaps 20 apples a year).
It's OK in pots. It's susceptible to tomato ring spot
virus.

M9

The best known
dwarfing rootstock. This is the rootstock used at
Brogdale, UK, for the National Fruit Collection. It is a
cross between a French tree, "Jaune de Metz", and the
"Paradise" apple of ancient Persia. It is known as the
"Paradise" stock of Europe. It fruits when very young,
is fairly hardy, tolerant of wet but not drought, and
compatible with all apple scions. It has to be staked
strongly, its roots are slightly brittle, and it is
about 8-9 feet tall at maturity on an ideal soil.

M26

A cross of M9 and
M16. Used in irrigated orchards on well drained solis.
Fruits early in its life, needs permanent staking,
hardy. Susceptible to crown rot and fireblight. M26 is
not so good in wet, clay soils where it is rather
moribund. Produces burr knots - the beginnings of little
aerial roots - which attract pests and which can
compromise the tree; these can be sliced off carefully
in the garden situation. Planting deeper (so less
rootstock is exposed) helps solve the problem
commercially. Reaches about 8-10ft if unpruned. OK in
pots.

MM106

A hydbid of Northern
Spy (English dessert apple) and English Broadleaf. Well
anchored, fruits early in its life, few suckers, fruit
matures late, trees have a long season, OK in pots with
less vigorous varieties. Susceptible to crown and root
rot. Recommended by my supplier as a substitute for M26
in wet, cold soil : a little more vigorous. Semidwarf.
9-11ft high. Resistant to woolly aphid.

M7

Descended from a
French tree, "Doucin Reinette". Very hardy. Likes deep,
well drained soils. It suckers badly, is prone to crown
gall, is resistant to fireblight, and tolerates wet
soils. About the same size as MM106 (semidwarf). Has
been used in New Hampshire, USA for 40 years. Fruits in
5th year. Has a tendency to lean. Most trees are very
fruitful. Needs staking for first 4-5 years.

MM111

Northern Spy hybrid.
About 75% of full size; too large for small gardens.
Prone to burr knots. 10-12ft. Semi-dwarfing or
half-standard. Resistant to woolly aphid.

M2

Very similar in size
and vigour to MM111. Not quite so vigorous as M25.

M25

Full size tree;
avoid unless you have a large space in which to grow it.
Very vigorous; typically 12-15ft high; can be bigger
depending on variety, large, heavy, spreading tree.

Good fertile soil. Ground should be cleared of weeds and grass. Staking required for the first 5 years. Very sensitive to systemic herbicides such as Glyphosate the use of which should be avoided around young trees.

Mature height

8-10ft (2.4-3m)

Spread

10ft (3m)

Planting distance

10ft (3m) apart, 12ft (3.6m) between rows

Mature yield

Bearing age

3 years

Suitable forms

Bush, small fan

Cherry:
Colt
(Semi-vigorous)

Requirements

Suitable for a wide range of soils including relatively poor soils and grassed orchards. Staking preferable but not necessary if planted as a one year old. Stake for first 3 years if planted as 2/3 year trees.

Mature height

12-15ft (3-4.5m)

Spread

15ft (4.5m)

Planting distance

15ft (4.5m) apart, 20ft (6.5m) between rows

Mature yield

Bearing age

4/5 years

Suitable forms

Half standard, bush

Cherry:
F12/1
(Very vigorous)

Requirements

Suitable for a wide range of soils including poor soils and grassed orchards. Staking preferable but not necessary if planted as a one year old. Stake for first 3 years if planted as 2/3 year trees.